The present invention relates to a "floating" current source, that is a source of current that is not directly tied to a power supply, and more particularly to an improved floating current transfer device for supplying stimulating signals to a cochlear electrode.
U.S. patent application Ser. No. 07/411,563, filed Sept. 22, 1989, describes a cochlea stimulating system for improving the hearing of the hearing impaired. One feature of the system described in the patent application is the use of floating current transfer devices for supplying stimulating signals to electrodes implanted within a cochlea of a hearing impaired person. The use of such devices enables an implantable cochlea stimulator to stimulate pairs of electrodes independent of the current flow in other pairs of electrodes and also allows for the exact control of current in each output stage, with no direct current path back to a main power supply or to any other output stage. This eliminates any concern of undesired currents flowing between any of the output stages.
The present invention is directed to a preferred form of such a floating current source and transfer device.